Some cool science that was published this week: using quantum dots to hunt cancer, plants that can sniff out predators, and how gut bacteria could let you live longer!
How smart is the average plant? Increasingly, biologists are uncovering surprising mechanisms by which plants sense and react to their environment. Scientists report that goldenrod plants are able to sense a chemical signal produced by a plant-munching insect. After “smelling” the insect, the plant mounts an immune response to protect it from future insect insult.
Bacteria often like to hang out together in biofilms, or large mats of cells that cooperate to share resources and food. However, bacteria that engage in this kind of communal lifestyle must be constantly wary of freeloaders who attempt to associate with the group without paying dues. Researchers report that when biofilms experience a change in ionic composition in their environment (during a transition from fresh to salt water, for example), cells that are actively producing proteins important for the structure of the biofilm are so closely associated that they push out freeloaders not producing any protein.
It’s hard to locate a tumor within the expanse of the human body, and even harder to take a clear picture of it. Scientists have developed a new method that uses quantum dots to image tumors in higher resolution than before in human patients. Quantum dots are particles a few nanometers in size, whose electrochemical properties set them apart from most other small molecules, and allow them to be imaged with ease. To image tumors in patients, scientists attach quantum dots onto particular molecules that are normally gobbled up by tumor cells. After the tumor has internalized the molecule with the dot, a chemical that quenches the quantum dots’ ability to fluoresce is injected into the patient, to remove any circulating quantum dot background fluorescence not associated with the tumor. Researchers hope the method increases the ease of early cancer detection.
Although most of us like to consider ourselves human, the bacterial cells associated with our bodies greatly outnumber our own cells, and are central to our health. This week, scientists reported that the composition of bacterial communities inside the guts of fish influences fish lifespan. Transplantation of bacteria from young fish into older fish increased the lifespan of the recipients. Researchers implicated bacterial diversity in conferring the life lengthening, showing that older fish have less-diverse microbiomes than their younger counterparts. Eat your yogurt!
Plants and fungi are close colleagues, forming tight interactions deep underground that facilitates the sharing of key nutrients. This week, it was discovered that in addition to sharing carbohydrates, plants and fungi also swap fatty acids. This deepens the overlap in metabolisms between two distantly related kingdoms of life.
You rely on your inner ear for the perception of sound as well as gravity, and without the flawless construction of a massively complex structure, you’d be unable to enjoy both Mozart and any perception of steadiness. Such an important organ needs to be built with high fidelity, but how does the inner ear know when to stop growing when it reaches the appropriate size? Scientists blended mathematical models with biology to show that elastic force on cells in the developing ear signals when the correct organ size has been achieved. They cultured inner ear tissue from mice on gels whose firmness could be manipulated, and were able to change the final size of the organ by altering the firmness of the material around the ear.